Thionyl chloride apparatus

Place 20 g. of dry powdered benzoic acid in C, add 15 ml. (25 g., i.e., a 30% excess) of thionyl chloride and some fragments of porcelain, and then clamp the apparatus on a boiling water-bath as shown so that no liquid can collect in the side-arm of C. Heat for one hour (with occasional gentle shaking), by which time the evolution of gas will be complete. Cool the flask C, detach the condenser and fit it to the side-arm for distillation, using a 360° thermometer for the neck of C. To the lower end of the condenser fit a small conical flask G (Fig. 67(B)) by a cork carrying also a calcium chloride tube. 

Fit up the apparatus shown in Fig. Ill, 31, 1 the capacity of the Claisen flask should be 100 ml. Place 40 g. (24-6 ml.) of redistilled thionyl chloride in the flask and 60 g. (62 ml.) of dry n-butyl alcohol (b.p. 116-117°) in the dropping funnel. Cool the flask in ice and add the n-butyl alcohol, with frequent shaking, over 1 hour (1). Reflux the mixture gently for 1 hour to complete the reaction and to remove the residual hydrogen chloride. Arrange the apparatus for distillation, and distil under normal pressure until the temperature rises to 120° then distil under diminished pressure (Fig. 11, 20, 1) and collect the di-n-butyl sulphite at 116-118°/20 mm. The yield is 66 g. 

Fit a reflux condenser into the short neck of a 125 ml. Claisen flask, a separatory funnel into the long neck, and plug the side arm with a small cork (compare Fig. Ill, 31, 1). Place 58 g. (62 ml.) of commercial n-caproic acid (1) in the flask and heat on a water hath. Add 75 g. (46 ml.) of redistilled thionyl chloride through the separatory funnel during 45 minutes shake the flask from time to time to ensure thorough mixing. Reflux the mixture for 30 minutes. Arrange the apparatus for distillation from an air bath (Fig. II, 5, 3) the excess of thionyl chloride passes over flrst, followed by n-caproyl chloride at 145-155° (mainly at 150-155°). The yield of acid chloride is 56 g. 

Place 29 g. of n-caproamide (Section 111,109) into a 200 ml. distilling flask, and assemble the apparatus shown in Fig. Ill, 28, 1. Remove the trap momentarily and introduce 45 g. (27-5 ml.) of redistilled thionyl chloride no apparent reaction takes place in the cold. Warm the mixture on a water bath or by means of a small flame for 1 hour. Arrange the apparatus for distillation and distil oflF the excess of thionyl chloride (t.c., until the temperature reaches about 90°) and allow to cool. When cold, transfer the residue to a 100 ml. distilling flask (1). Distil from an air bath (Fig. II, 5, 3) the n-capronitrile passes over at 161-163° (2). The yield is 21 g. 

A. 2-(2,3-Dimethoxyphenyl)-4,4-dimethyl-2-oxazoline. To a 100-mL. round-bottomed flask, fitted with a magnetic stirring bar and a reflux condenser and placed in an ice-water bath, is added 24.5 g (0.206 mol) of thionyl chloride (Note 1). To this is added 12.2 g (0.067 mol) of 2,3-dimethoxybenzoic acid (Note 2). The resulting mixture is stirred at 0°C for 1 hr and then at room temperature for 24 hr. Excess thionyl chloride is removed by rotary evaporation (HOOD ) and the residue is distilled using a Kugelrohr apparatus at 105°C (0.05 mm) to give 12.7-13.1 g of 2,3-dimethoxybenzoyl chloride, which crystallizes on cooling (Note 3). 

Seventy grams (0.25 mole) of oleic acid (Note 1) is placed in the dropping funnel H of the tangential apparatus (Fig. 2 Note 2). The thionyl chloride distillation is started and regulated (Note 2) the upper part of the column should be filled with the vapor, and reflux should be constant and steady. The acid is dropped in at the top of the column over a period of 35 minutes (120 g. per hour). The product that collects in the receiver I contains about 25-27% of thionyl chloride (Note 2) if the heated lower leg K is employed. The product in... 

This modification of the continuous reactor (cf. benzoylacetanilide, p. 2) with countercurrent distillation is preferred for reactions in which a large amount of solvent or excess of one reactant is essential, but increase of total volume is undesirable. It is especially useful if the substances involved are heat-sensitive with this apparatus the reactants are heated for only a few minutes at most. It is particularly applicable to the preparation of acid chlorides from carboxylic acids and thionyl chloride (cf. Notes 3 and 4). An indefinite amount of product can be prepared by replenishing the reactants as they are consumed. 

Preparation of Thionyl Chloride. Assemble an apparatus as-shown in Fig. 70a and check its tightness. Put 15 g of phosphorus pentachloride onto the bottom of dry retort 1. (This compound readily hydrolyzes ) Switch on water cooler 2. Pass a stream of thoroughly dried sulphur dioxide through the retort. What occurs When the reaction slows down, slightly heat the retort while carefully shaking it. Stop the heating after the entire phosphorus pentachloride reacts. Write the equation of the reaction. 

Fig. 70. Apparatuses for preparing thionyl chloride (a) and purifying it by distillation (6)...

Assemble an apparatus (see Fig. 21). Place the prepared vanadi-um(V) oxide into a flask and add 12 ml of freshly distilled thionyl chloride. Heat the flask in a water bath for three or four hours. Replace the reflux condenser with a dephlegmator provided with an inclined cooler (see Fig. 20). Distil off the fraction boiling at 126-127 °C by carefully heating the flask with the open flame of a burner. Transfer the collected liquid into a weighed drawn out test tube. (Wear eye protection, seal the substance in the presence of your instructor ) Weigh the ampoule with the substance and the remaining part of the tube. Calculate the yield in per cent. 

Fifty-five grams of tin (IV) chloride 5-hydrate are refluxed in an all-glass apparatus with lOOg of thionyl chloride for 3-4 hours [hood]. Moisture is excluded during this operation the reaction is over when no more acid vapors escape from the drying tube at the top of the condenser. The product is then fractionally distilled to remove the excess thionyl chloride which is collected up to 110°G the material boiling at 110-115°C must be colorless, otherwise a redistillation is necessary. 

Method 1. Commercial thionyl chloride is first fractionated in an all-glass apparatus from quinoline in order to remove acid impurities (50g of thionyl chloride from 10 ml of quinoline) the receiver is protected from the entrance of moisture by a guard-tube, filled with anhydrous calcium chloride. The distillate is then refractionated as before from boiled linseed oil (50 g of thionyl chloride from 20 ml of linseed oil), the fraction, b.p. 76-78 °C, being collected. 

Reaction in the absence of catalyst. Assemble in a fume cupboard a 500-ml three-necked flask equipped with a sealed stirrer unit, a double surface reflux condenser and a separatory funnel fit the condenser and the funnel with calcium chloride guard-tubes. Place 179 g (109.5 ml, 1.5 mol) of redistilled thionyl chloride in the flask and 51 g (62.5 ml, 0.5 mol) of hexan-l-ol, b.p. 156-158 °C, in the separatory funnel. Add the alcohol with stirring during 2 hours there is a slight evolution of heat, sulphur dioxide is evolved and the liquid darkens considerably. When all the alcohol has been added, reflux the mixture for 2 hours. Rearrange the apparatus for distillation, and distil slowly the excess of thionyl chloride passes over below 80 °C, followed by a small fraction up to 120 °C and finally the crude 1-chlorohexane at 132— 134 °C. Wash the last-named successively with water, 10 per cent sodium carbonate solution, and twice with water. Dry with anhydrous calcium chloride and distil through a short fractionating column. Pure 1-chlorohexane passes over at 133-134 °C. The yield is 36 g (60%). 

Sebacoy I chloride. Convert 20 g (0.1 mol) of sebacic acid (Expt 5.131) into the corresponding acid chloride by heating it on a water bath in a flask fitted with a reflux condenser (protected with a calcium chloride tube) with 20 ml of thionyl chloride the apparatus should be assembled in a fume cupboard. Purify the product by distillation under reduced pressure (use appropriate traps to protect the pump from the fumes of hydrogen chloride and sulphur dioxide). Collect the sebacoyl chloride as a fraction of b.p. 140-143 °C/ 2mmHg the yield is 18 g (77%). 

Fit a 100-ml two-necked flask with a dropping funnel and a reflux condenser connected at the top to a gas absorption trap (Fig. 2.61). Place 36g (21.5ml, 0.3 mol) of redistilled thionyl chloride in the flask and 22 g (23 ml, 0.25 mol) of butyric acid in the separatory funnel. Heat the flask gently on a water bath, and add the butyric acid during the course of 30-40 minutes (1). When all the acid has been introduced, heat on a water bath for 30 minutes. Rearrange the apparatus and distil collect the crude acid chloride boiling between 70 and 110°C. Finally, redistil from a flask provided with a short fractionating column and collect the butyryl chloride at 100-101 °C. The yield is 23 g (86%). 

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